The invention relates to the fields of cell growth and detection.
In many industries, particularly the food, beverage, healthcare, electronic, and pharmaceutical industries, it is essential to rapidly analyze samples for the degree of contamination by microorganisms, such as bacteria, yeasts, or molds.
One microbial culture technique, called microbial enumeration or colony counting, quantifies the number of microbial cells in a sample. The microbial enumeration method, which is based on in situ microbial replication, generally yields one visually detectable “colony” for each culturable microbial cell or clump of cells in the sample, referred to as a colony forming unit or CFU. Thus, counting the visible colonies allows microbiologists to determine the number of microbial CFUs in a sample accurately. To perform microbial enumeration, bacterial cells can be dispersed on the surface of nutrient agar in Petri dishes (“agar plates”) and incubated under conditions that permit in situ bacterial replication. Microbial enumeration is simple, ultra-sensitive, inexpensive, and quantitative but is also typically slow. The long time required results in increased costs in healthcare and in manufacturing.
There is a need for additional culturing devices and methods for microbial enumeration.